Background and Objectives of DEOS
The objectives of this project are to develop a method to continuously provide services that meet users requirements by accommodating the system to ever-changing objectives and environments.
Computer systems today face increases in the following problematic characteristics;
- Complexity of systems,
- Size of systems,
- Connection to and dependency on network,
- Black-box components or subsystems, and
- Dependency on legacy codes.
These increases make it extremely difficult to understand the whole systems, to analyze every detail of the system, and to build the system with perfect understanding of every component.
On top of the above mentioned, the following changes of the system environment increase the uncertainty in system operation.
- Diversification of services
- Change of requirements from service users
- Change of rules or systems of society
- Change of business objectives
- Change of the specifications or functions of other related systems
It is appropriate to assume that the functions, structure, and boundaries of the systems of today are not fixed and definable, but rather will change over time (open system or ever-changing system). The incompleteness and uncertainty caused by those characteristics are not completely avoidable and the systems inherently contain the factors for future failures (Factors in Open Systems Failure).
We think it is important to keep making our best efforts to prevent these problem factors from causing failures, to take appropriate and quick action when failures occur, to minimize damage, to provide the services expected by users as safely and continuously as possible, and to maintain accountability for the system operations and processes.
Until now, technologies for improving the safety and security of systems have been researched, discussed and developed with a focus on incidental and intentional faults. Our approach is to improve the dependability of systems by minimizing the factors that specifically cause open systems failures and by minimizing the damage due to open systems failures, concentrating on open systems failures resulting from incompleteness and uncertainty. Indeed, Open Systems Dependability further enhances traditional dependability.
